This specification is used to describe the composition of the final application in term of components that should be instantiated in which isolate of which node.
A composition.js file which describes the composition of the application is located on the conf directory of the Top Composer node. The Top Composer dispatchs this specification to other nodes of the application.
Composition
{
// Composition's name
"name": "composition-name",
// Top composite
"root": { /* see 'composite' */ }
}Composite
{
// Name of composite
"name": "composite1",
// List of components
"components" : [ /* see 'components' */ ],
// List of sub-composites
"composites" : [
{
"name": "subcomposite",
"components" : [ /* ... */ ]
// this composite hasn't sub-composites.
}
]
}Components
{
// Name of the component
"name" : "aggregator-UI",
// Name of its Component Factory
"factory" : "demo-sensor-aggregator-ui-factory",
// Indication on the implementation language
"language" : "python",
// Location on a precise isolate
"isolate" : "aggregator.ui",
// Location on a precise node
"node" : "central",
// Initial configuration of the component
"properties" : {
"servlet.path" : "/sensors"
},
// Wiring with another component named 'aggregtor'
// which can be found in any composite of this composition
"wires" : {
"_aggregator" : "aggregator"
},
"filters" : {
"_handler": "(ready=1)"
}
}import-files
base.js
{
"root": "root",
"imported": {
"top-value": "top",
"answer": 42,
// Import from another file
"import-files": ["imported.js"]
}
}imported.js
{
// New property
"hello": "World",
// This value will be overloaded by the high level property's value
"answer": 51
}Obtained result :
{
"root": "root",
"imported": {
// Non modified value
"top-value": "top",
// Conserved value
"answer": 42,
// New property
"hello": "world"
}
}Complete example
{
"name" : "hello-world",
"root" : {
"name" : "hello-worldd-composition",
"components" : [
{
"name" : "Hello_Components",
"factory" : "hello_components_factory",
"node" : "node1",
"isolate": "web"
}, {
"name" : "A_component",
"factory" : "component_a_factory",
"node" : "node1"
}, {
"name" : "B_component",
"factory" : "component_b_factory",
"node" : "node1"
}, {
"name" : "E_component",
"factory" : "component_e_factory",
"node" : "node1"
}, {
"name" : "C_component",
"factory" : "component_c_factory",
"node" : "node2"
}, {
"name" : "D_component",
"factory" : "component_d_factory",
"node" : "node2"
}
]
}
}
